The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By using the USDA zone info for Billings it's possible to figure out when to plant garden mums.

Planting Calendar for Garden Mums

Frost tolerance for garden mums:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Garden Mums are moderately cold tolerant which means that you can plant them earlier than other plants that might not handle the cold.

The earliest that you can plant garden mums in Billings is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant garden mums and expect a good harvest is probably August. Any later than that and your garden mums may not have a chance to grow to maturity. If you are starting your garden mums indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost is on May 15 in Billings. It might get as low as -25°F during the coldest months of winter.

Since the USDA zone info for Billings is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Billings you get a frost after May 15 so make sure that you are prepared to cover your garden mums if you have a surprise late frost.

USDA Zone Info for Billings

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Billings

You may be interested in your other planting guides for Billings.